ASSOCIATED PRESS WRITER

KAREN BALL

WASHINGTON (AP)—Greeted with an unusual ovation from lawmakers, Hillary Rodham Clinton began the selling of her husband’s health care plan in Congress on Tuesday. She acknowledged room to negotiate but insisted action must be swift.

‘‘As we sit here today, literally hundreds and hundreds of Americans will lose their health care,’‘ Mrs. Clinton said as the House Ways and Means Committee opened hearings on President Clinton’s package. It is designed to provide coverage for all, rein in costs and spark competition.

Mrs. Clinton conceded the plan would probably cost one in 10 Americans more money for the same level of benefits.

‘‘We think we’re being as fair as we can, but I want to be honest,’‘ the first lady told the House Energy and Commerce Committee, where she had headed after the Ways and Means panel.

About 10 percent to 12 percent of the population—mostly young, healthy people who have benefited from the current system—will have to pay more for the same benefits, Mrs. Clinton said.

Roughly 63 percent to 65 percent of people will pay the same or less for better benefits, she said, but 20 to 22 percent will probably pay a little more money for better benefits, she said.

Mrs. Clinton, breaking ground as a first lady, spent more than four hours answering questions from the two panels. She goes to three more congressional committees over the next two days as Congress starts wading into the issue. No action is expected until well into next year.

She was peppered with questions doubting the administration’s wisdom on various provisions of the plan. She repeatedly, methodically laid out why the White House had chosen its approach.

She told lawmakers the details of the plan are open to negotiation, but she defended Clinton’s call for sacrifice by Americans in order to overhaul the nation’s $900 billion system.

‘‘The upcoming debate is not about any one set of citizens but all of us,’‘ Mrs. Clinton said.

While Democrats and Republicans alike expressed reservations—nearly every question from the 38 Ways and Means members raised a concern—lawmakers practically gushed at Mrs. Clinton’s knowledge and handling of the complex subject. They gave the witness a rare round of applause.

Chairman Dan Rostenkowski, D-Ill., cracked that ‘‘in the very near future, the president will be known as your husband. ‘Who’s that fellow? That’s Hillary’s husband.’‘’

And Rep. Richard Neal, D-Mass., joked that she knew all the answers and should go on the quiz show ‘‘Jeopardy!’‘ in her next life.

At the Energy and Commerce hearing, Rep. Cliff Stearns, R-Fla., noted that many Cabinet members show up to testify surrounded by aides who whisper responses to lawmakers’ questions in their ears.

‘‘You’re making a winning statement by showing up all by yourself at that table,’‘ he said.

In the huge Ways and Means hearing room, Rostenkowski, with hand on gavel, kept members’ questions to within one minute. He even tapped Mrs. Clinton to silence a time or two when she went over her one-minute response time.

‘‘We could go on, but my red light is on,’‘ Mrs. Clinton said, noting she was out of time as she tried to douse Rep. Sam Gibbons’ concerns about how the Clinton plan would trim Medicare costs.

Other lawmakers had suspicions in a wide-ranging preview of where some of the battles in Congress are likely to be fought.

Even Rostenkowski said he was concerned about the impact on businesses back in Chicago; Rep. Pete Stark, D-Calif., who heads the Medicare subcommittee that will play a key role, sounded off about putting states in charge, complaining his own governor has no interest in participating.

Rep. Jim McDermott, D-Wash., who heads the ‘‘single payer’‘ faction of lawmakers pushing for a government-run system, wanted to know how the government could force a self-employed person to pay premiums. What guarantees are there a contractor making $22,000 a year trying to support a family could pay his $4,000 family premium? McDermott asked.

Mrs. Clinton stayed unflappable throughout. She tried to assure McDermott that the contractor would get a small-business subsidy and tax break The incentives would be there for him to get coverage for his family, she said.

Small businesses will in the end be better off because they’ll get the same breaks as large companies, Mrs. Clinton said.

A tobacco-state lawmaker, Rep. Jim Bunning, R-Ky., complained about singling out tobacco for a tax increase. He suggested products high in sugar, caffeine and cholesterol be hit, too, on grounds that they can cause health problems.

Mrs. Clinton noted that tobacco is considered unhealthful, even in moderation. ‘‘There is no free lunch,’‘ she said, and told Bunning, in a remark that brought some chuckles, “If there is a way to ever come up with a tax on the substances you just mentioned, we’ll be glad to look at it.”

Rep. Thomas Bliley, R-Va., whipped out charts and asked how the administration’s plan could keep medical costs to 1 percent more than inflation, when costs have been rising 4 percent above that in Canada and Great Britain.

“Mr. Bliley, that’s an excellent question. I really appreciate your asking that,” she said, adding that the Clinton plan envisions big savings by ridding the system of waste and unnecessary medical procedures and streamlining administration costs.

Rep. Bill Archer, R-Texas, the Ways and Means’ ranking Republican, said he was concerned that the White House plan would fatten government bureaucracy and doubted the wisdom of trying out such a huge change without a pilot run.

“Health reform isn’t a product to be packaged and sold like a toaster on the Home Shopping Network—we’ve got to know how it works, what it will really cost … and how these costs are going to be paid for,” Archer said.